QGIS/python/plugins/sextante/saga/help/GridProximityBuffer.html

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<h1 class='module'>Grid Proximity Buffer</h1>
<div class='author'>Copyrights (c) 2006 by Volker Wichmann</div>
<div class='description'>This module calculates the euclidian distance within a buffer distance from all NoData cells to the nearest valid neighbour in a source grid. Additionally, the source cells define the zones that will be used in the euclidean allocation calculations. Cell values in the source grid are treated as IDs (integer) and used in the allocation grid to identify the grid value of the closest source cell. If a cell is at an equal distance to two or more sources, the cell is assigned to the source that is first encountered in the modules scanning process. The buffer grid is a reclassification of the distance grid using a user specified equidistance to create a set of discrete distance buffers from source features. The buffer zones are coded with the maximum distance value of the corresponding buffer interval. The output value type for the distance grid is floating-point. The output values for the allocation and buffer grid are of type integer. The duration of module execution is dependent on the number of source cells and the buffer distance.</div>
<h2>Parameters</h2>
<dl class='parameters'>
<dt>Grid system <div class='type'>Grid system</div></dt><dd>Grid system <div class='constraints'></div></dd>
<dt>Source Grid <div class='type'>Input Grid</div></dt><dd>Grid with features to be buffered [Category/NoData] <div class='constraints'></div></dd>
<dt>Distance Grid <div class='type'>Output Grid</div></dt><dd>Grid with euclidian distance to nearest source cell [grid units] <div class='constraints'></div></dd>
<dt>Allocation Grid <div class='type'>Output Grid</div></dt><dd>Grid with category of nearest source cell [Category] <div class='constraints'></div></dd>
<dt>Buffer Grid <div class='type'>Output Grid</div></dt><dd>Reclassification of distance grid to buffer zones with a width equal to the equidistance value. <div class='constraints'></div></dd>
<dt>Buffer distance <div class='type'>Floating point</div></dt><dd>Buffer distance (grid units). <div class='constraints'></div></dd>
<dt>Equidistance <div class='type'>Integer</div></dt><dd>Reclassify buffer distance to intervals of euqidistance ... <div class='constraints'></div></dd>
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